West Nile Virus

What would you like to do?

What would you like to do?

What you need to know

What you need to know

Page Content

​West Nile virus is carried by Culex mosquitoes. It can cause serious disease and death in people. You can find this virus in all the lower 48 states. The Nebraska Department Health and Human Services (DHHS), Division of Public Health tracks and helps prevent the spread of West Nile virus (WNV).

West Nile Virus and Your Health

Most people who become infected with West Nile virus do not develop symptoms. Mild cases of West Nile infection can include slight fever and/or headache. Severe infections, which usually occur five to 15 days after exposure, can lead to rapid onset of high fever, head and body aches. There is no specific treatment for West Nile virus, other than to treat the symptoms and provide supportive care. Those at highest risk of becoming seriously ill from West Nile infection are people over age 50.

Transmission

Mosquitoes acquire West Nile virus from infected birds and then pass it onto other birds, animals and/or people. View the transmission cycle of West Nile virus for additional information.

Prevention

The best defense against West Nile virus is protecting yourself with repellent and not giving mosquitoes a place to lay eggs and develop. Visit the West Nile virus Prevention page to find tips to reduce your risk and control mosquitos.

Frequently Asked Questions

West Nile virus is a mosquito-borne disease that can potentially cause encephalitis, or a brain infection. Mosquitoes acquire the virus from feeding on infected birds. They pass it on by biting other birds, animals and/or people. It is not spread by person-to-person contact. There is no evidence that people can acquire the virus by handling infected animals.

West Nile virus cases occur mostly in the late summer and early fall, even though the mosquito season technically runs from April to October.

People can only get the West Nile virus after the bite of an infected mosquito. There is no evidence that people can get West Nile virus from other infected animals or people, or that people can transmit the West Nile virus to other animals, birds, or people.

Anyone can get infected with West Nile virus. However, people over age 50 have the highest risk of developing a severe illness because as we age, our bodies have a harder time fighting off disease. People with compromised immune systems are also at increased risk.

There are about 50 different species of mosquitoes in Nebraska. While most do not transmit West Nile virus, several species can transmit it.

Mosquitoes lay their eggs in stagnant water around houses. Adult mosquitoes can also find a home in weeds, tall grass, shrubbery and discarded tires. By eliminating breeding places for mosquitoes, we can go a long way to prevent West Nile virus.

Mosquitoes breed in standing water. Even a small bucket with stagnant water in it for seven days can become home to up to 1,000 mosquitoes. Here are some easy tips to eliminate standing water:

Dispose of cans, plastic containers, ceramic pots or similar water-holding containers that have piled up on your property. Do not overlook containers that have become overgrown by aquatic vegetation.

Pay special attention to any discarded tires on your property.

Drill holes in the bottom of outdoor containers for recycling. If the drainage holes are on the side, a container can collect enough water for mosquitoes to breed.

Clean clogged roof gutters regularly (spring and fall), particularly if the leaves from surrounding trees tend to plug up the drains. If overlooked, roof gutters can produce millions of mosquitoes each season.

Turn over plastic wading pools when not in use. A wading pool becomes a mosquito producer if it is not used on a regular basis.

Turn over wheelbarrows and do not allow water to stagnate in birdbaths. Both provide breeding grounds for domestic mosquitoes.

Air out ornamental pools or stock them with fish. Water gardens are fashionable but become major mosquito producers if you let them stagnate.

Clean and chlorinate swimming pools that are not in use. Leaving a swimming pool untended for a month can produce enough mosquitoes to result in neighborhood-wide complaints. Even the covers for swimming pools may collect water and allow mosquitoes to breed.

Use landscaping to eliminate standing water that collects on your property. Mosquitoes will develop in any puddle that lasts for more than four days.

The best way to defend yourself against the Virus is to use a mosquito repellant containing DEET. The CDC has also approved picaridin and oil of lemon eucalyptus.

You do not need to limit any outdoor activities, unless local officials advise you otherwise. However, you can and should try to reduce your risk of being bitten by mosquitoes. In addition to reducing stagnant water in your yard, make sure all windows and doors have screens, and that all screens are in good repair.

If West Nile virus is found in your area:

Take normal steps to prevent insect bites.

Wear shoes, socks, long pants and a long-sleeved shirt when outdoors for long periods of time, or when mosquitoes are most active.

Consider the use of mosquito repellent, according to directions, when you need to be outdoors. Wash all treated skin and clothing when returning indoors.

Electromagnetic and ultrasound devices and Vitamin B are not effective in preventing mosquito bites.